| 1 | Gideon | Fell | Protagonist. Doctor of Philosophy, expert on crime. |
| | Hadley | | The chief inspector. |
| | Tad | Rampol | Fell's companion. |
| | Martin | Starbeth | Murdered. |
| | Dorothy | Starbeth | Martin's sister. Rampole's girlfriend. |
| | William | Bitton | The book collector. The owner of the stolen manuscript. |
| | The | Mad Hatter | The Hat thief. |
| | Philip | Driscoll | William's nephew. A news reporter. |
| | Thomas | Sparkle | The police constable. |
| | James | McGuire | A police constable. |
| | Jennifer | | The horse. |
| | Isaac | Simonides-Levy | A well-known member of the stock exchange. |
| 2 | Edgar Allan | Poe | A famous poet. |
| | Dr. | Masters | The Philadelphia collector. |
| | Prof. | Hervey | The leading authorities on Poe. |
| | Allen | | The leading authorities on Poe. |
| | Dr. | Robertson | The leading authorities on Poe. |
| | Sheila | Bitton | William's daughter. |
| | Lester | Bitton | William's brother. |
| | Julius | Arbor | The American collector. |
| | General | Mason | William's friend. The deputy governor of London. |
| | Robert | Devereux | Earl of Essex. |
| 3 | Anders | | The police sergeant. |
| | Robert | Dalrye | General Mason's secretary. Aka: Bob. |
| | Leonard | Haldyne | The keeper of the jewel house. |
| | Dr. | Benedict | The chief-of-staff in charge of the army hospital. |
| | Mr. | Radburn | The chief warden. |
| 4 | John | Bronlow | One of Dalrye's colleagues. |
| | Parker | | One of General Mason's assistants. |
| 5 | Amanda Georgette | Larkin | One of the tower's visitors. Philip's neighbor. Aka: Amanda Leeds, Georgie Simpson, Emmy. |
| | Laura | Bitton | William's sister-in-law. Lester's wife. |
| | Betts | | The police sergeant. |
| 6 | Hamper | | A police sergeant. |
| | Doctor | Watson | The police surgeon. |
| 7 | Mary | | The mystery woman. |
| 8 | Joseph | McCartney | The owner of the property where Poe's manuscript was found. |
| | Daniel | Spengler | Julius's friend. |
| | Mrs. | Spengler | Mr. Spengler's wife. |
| 9 | Ian | Hamilton | A General. |
| 10 | Sylvia | | Dorothy's former schoolmate. |
| | Somers | | The man who investigated Larkin. |
| | Mary | Tudor | Philip II's wife. |
| | Philip II | | King of Spain. |
| 12 | Theopilus | Marks | William's valet. |
| 14 | Lord | Sandival | Mark's former employer. |
| 17 | Mr. | Hobbes | The Bitton's butler. |
| | Margaret | | Sheila's friend. |
